Technical Abstract:
Transmission of Salmonella and Campylobacter to humans can occur by many routes, including consumption of food animal products or raw produce contaminated with animal waste, contact with animals and their environment, and contaminated water; including surface waters that are potential reservoirs and transmission routes for these pathogens. The presence of the pathogens Salmonella and Campylobacter in the stream network of the Satilla River Basin (SRB) were monitored monthly from August 2007 to August 2009 to ascertain potential relationships between these pathogens and varying levels of agriculture and poultry processing facilities within the SRB. Watersheds were sampled that: 1) represent agricultural areas receiving poultry litter application, 2) agricultural areas with poultry houses and receiving poultry litter application, 3) reference areas with little or no agricultural activity, 4) a small watershed receiving direct discharge from the city of Douglas municipal wastewater treatment plant (WWTP) that received poultry slaughterhouse waste, and 5) larger watersheds on the main channel of the Satilla River and a major tributary (Seventeen Mile River). A combination of enrichment and conventional cultural methods was used for confirmation and identification of Salmonella, whereas Campylobacter detection consisted of enrichment and conventional polymerase chain reaction (PCR) for confirmation. In our investigation, pathogens were frequently detected at all sites monitored. Generally, pathogen prevalence increased from upstream to downstream in the watershed, likely reflecting the cumulative effect of inputs. Salmonella occurrence ranged from 17% (N = 23) at site 2 (no poultry houses) to 61% (N = 23) positive both immediately downstream of the WWTP, and on a sub-watershed containing 173 poultry houses. Campylobacter detection ranged from 43% positive (N = 14) at three sites including the control station with no poultry houses to 79% (N = 14) positive at site 8 upstream of the WWTP on the Seventeen Mile River within a sub-watershed containing 98 poultry houses. Continued research will investigate the potential human and animal health risk from Salmonella and Campylobacter within the SRB.